[GTL]

i studied a bit of biology and anthropology in college and most people believe that evolution has a purpose. all scientific study up to this point has indicated that evolutionary forces have no goal or purpose. they are more akin to gravity or magnetism. they just act.

the interesting thing, is that the different evolutionary forces cause different evolutionary changes. for example, natural selection tends to keep a species genetically similar to past generations. for the most part animals with mutations and other genetic differences are not procreating. most changes are caused by other forces of evolution. often times what creates a new species is simply a geographic isolation from a main population.

this is obviously not always the case though.

also, people arguing that human beings are no longer undergoing evolution because technology makes our lives too easy are flat out wrong. the reason why european diseases wiped out the majority of the indigenous population in the Americas most likely has an evolutionary explanation. City living in Europe caused the proliferation of epidemic diseases (they evolved from diseases in animal populations). This made death from disease the main cause of death in Europe. Over time, European populations evolved and developed immunitites to many of the diseases. In the Americas there were very few large cities, so there were not similar immunities.

In more modern times, scientists have documented genetic changes in African American populations with regard to the genes that code for sickle cell. This is another evolution tied closely to epidemic disease. having some sickle cells helps with immunity to Malaria, therefore the gene is present in most populations where you find the disease. The rate of African Americans who carry the gene has been decreasing in the Americas because there is no risk of Malaria.

Again, these changes weren't caused because people decided, I don't want to get sick let me switch my genes. It was just caused because of different forces acting on large populations.